Of course no country has such an obligation per se. But if your government constantly attacks my infrastructure, why oh why should I even consider paying a penny for your service? Given that many American companies still market to users outside the US, this nevertheless seems to be the overall expectation.

It is not about spying or not spying, it is about spying on legitimate targets. All countries (should) have obligations to basic human rights. If I were a head of state, I would expect the U.S. to attempt to spy on me (and I would expect my country to stop them). As an private individual, I very much have the same rights under the U.S. constitution as do U.S. citizens. It is not OK to violate my right to to be free from unreasonable search and seizure. They should have to get a warrant to spy on me, just as they (should) have to do for an American.

Quite right, it'd be a terrible spy agency with those restrictions. I have no issue with warranted investigations, or prosecuting people doing bad things.

I'm arguing that broad, warrantless surveillance is a horrible, chilling thing to be doing. The fact that everyone is doing it doesn't make me feel better.